@@ -1624,6 +1624,20 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
return zram_read_page(zram, bvec->bv_page, index, bio);
}
+static int write_same_filled_page(struct zram *zram, unsigned long fill,
+ u32 index)
+{
+ zram_slot_lock(zram, index);
+ zram_set_flag(zram, index, ZRAM_SAME);
+ zram_set_handle(zram, index, fill);
+ zram_slot_unlock(zram, index);
+
+ atomic64_inc(&zram->stats.same_pages);
+ atomic64_inc(&zram->stats.pages_stored);
+
+ return 0;
+}
+
static int zram_write_page(struct zram *zram, struct page *page, u32 index)
{
int ret = 0;
@@ -1633,7 +1647,7 @@ static int zram_write_page(struct zram *zram, struct page *page, u32 index)
void *src, *dst, *mem;
struct zcomp_strm *zstrm;
unsigned long element = 0;
- enum zram_pageflags flags = 0;
+ bool same_filled;
/* First, free memory allocated to this slot (if any) */
zram_slot_lock(zram, index);
@@ -1641,14 +1655,10 @@ static int zram_write_page(struct zram *zram, struct page *page, u32 index)
zram_slot_unlock(zram, index);
mem = kmap_local_page(page);
- if (page_same_filled(mem, &element)) {
- kunmap_local(mem);
- /* Free memory associated with this sector now. */
- flags = ZRAM_SAME;
- atomic64_inc(&zram->stats.same_pages);
- goto out;
- }
+ same_filled = page_same_filled(mem, &element);
kunmap_local(mem);
+ if (same_filled)
+ return write_same_filled_page(zram, element, index);
compress_again:
zstrm = zcomp_stream_get(zram->comps[ZRAM_PRIMARY_COMP]);
@@ -1727,7 +1737,7 @@ static int zram_write_page(struct zram *zram, struct page *page, u32 index)
zcomp_stream_put(zram->comps[ZRAM_PRIMARY_COMP]);
zs_unmap_object(zram->mem_pool, handle);
atomic64_add(comp_len, &zram->stats.compr_data_size);
-out:
+
zram_slot_lock(zram, index);
if (comp_len == PAGE_SIZE) {
zram_set_flag(zram, index, ZRAM_HUGE);
@@ -1735,13 +1745,8 @@ static int zram_write_page(struct zram *zram, struct page *page, u32 index)
atomic64_inc(&zram->stats.huge_pages_since);
}
- if (flags) {
- zram_set_flag(zram, index, flags);
- zram_set_handle(zram, index, element);
- } else {
- zram_set_handle(zram, index, handle);
- zram_set_obj_size(zram, index, comp_len);
- }
+ zram_set_handle(zram, index, handle);
+ zram_set_obj_size(zram, index, comp_len);
zram_slot_unlock(zram, index);
/* Update stats */
Handling of ZRAM_SAME now uses a goto to the final stages of zram_write_page() plus it introduces a branch and flags variable, which is not making the code any simpler. In reality, we can handle ZRAM_SAME immediately when we detect such pages and remove a goto and a branch. Factor out ZRAM_SAME handling into a separate routine to simplify zram_write_page(). Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> --- drivers/block/zram/zram_drv.c | 37 ++++++++++++++++++++--------------- 1 file changed, 21 insertions(+), 16 deletions(-)